Surface grinding machine



April 1941- P. v.' MILLER 2,238,704

SURFACE GRINDING MACHINE 22 24 "mflllllj i 1 N 11! mm .19 V W Illlllllllllllllll INVENTOR Pal! J/z'ller JP LLLYAJ;

I m ATTORNEYS A9141 1941- P. v. MILLER 2,238,704

SURFACE GRINDING MACHINE Filed Nov. 3, 1939 4 Sheets-$heet 2 INVENTORwalk/21171 M ATTORNEYS April 15, 1941. P. v MILLER SURFACE GRINDINGMACHINE Filed Nov. 3, 1939 4 Sheets-Sheet 5 mvslg-ron Paul Kflfzller MATTORNEYS/5 Patented Apr. 15, 1941 SURFACE GRINDING MACHINE Paul V.Miller, Woonsocket, R. L, assignor to Taft-Peirce Manufacturing Company.Woonsocket, R. L, a corporation of Rhode Island Application November 3,1939, Serial No. 302,645

4 Claims. I (01. 51-168) This invention relates to improvements ingrinding machines and more particularly to improvements in machines ofthe type known as surface grinders employing rotary grinding elements.

An object of the present invention is to provide a surface grinder inwhich the grinding element is tiltable, within limits, withoutsubstantial elevation or lowering of such element relative to a worksurface.

Another object of the invention is to provide a mounting for a rotarygrinding element, the mounting being of such character as to be tlltableabout an axis extending horizontally through the center of the grindingelement.

Another object of the invention is to provide a surface grinder in whichthe spindle for the rotary grinding element is carried in a blocksupported for tilting movement about an axis remote from one end of theblock.

An additional object of the invention is to provide in a surface grindera spindle carrying block held in assembly with a yoke by means ofsegments which are releasable and which can be locked to locate theblock any desired angular position relative to the yoke.

A further object of the invention is to provide a spindle carrying blockof such construction as to receive in the side walls thereof segmentstrips formedon different radii whereby the'block can be tilted on suchstrips about a common axis remote from one end of the block.

A still further object of the invention is to provide a combined safetyguard and lighting panel at one end of the table of a surface grinder,such panel having a source of illumination therein whereby alignment ofmaterial to be operated upon is facilitated.

Other features objects and advantages of the invention will be apparentby reference to the following detailed description read in the light ofthe accompanying drawings wherein Fig. 1 is a front perspective view ofa machin embodying the invention:

Fig. 2'is a side view of the same machine;

Fig. 3 is a section taken substantially on the line 3-3 of Fig.

Fig. 4 is a section taken substantially on the line 44 of Fig. 3;

Fig. 5 is a section taken substantially on thegenerally the base of themachine constructed substantially in the manner shown in Fig. 1, suchbase having movably mounted on a part thereof a table II and movablymounted on the table II a saddle l2 to receive achuck I4. The chuck 14can be of any desired type but preferably is of the magnetic type asshown in Fig. 1. Also secured to the base I0 at the rear thereof is acolumn I! mounted for vertical movement by any suitable mechanism.Movement of the table, the saddle and the column can be accomplishedthrough manipulation of the handles H which serve to operate mechanismsconnected to the respective parts. Inasmuch as the construction of thesevarious mechanisms forms no part of the present invention, they are notillustrated or described in detail herein.

The column is made up in part of vertically extending wing portions andrearwardly extending wall members 2| considerably thinner than the wings20. Near the top of the column, a yoke is provided, made up of parallelside walls 22 and a cap 24 secured across the top edges of the sidewalls. The walls of this yoke extend forward of the wings 20 asindicated at 25.

A spindle block indicated generally at 30 is mounted between the sidewalls 22 in a manner to be described later. This block, as shown clearlyin Fig. 6, has the top part thereof hollowed out as at 3| and isprovided with a through opening 32 in the lower part thereof. Opening 22is designed to receive a quill 34 of a cartridge type spindle and motorassembly, which quill 34 has a spindle 35 mounted therein for rotationin suitable bearings all sealed within the quill. Also fastened to therear end of the quill is a motor 36, the shaft of which is directlycoupled to the spindle 35 or, if desired, the spindle 35 may be integralwith the motor shaft, as is well known in this type of construction. Thequill 34 is held in the opening 32 by means of set screws 31 passingthrough the bottom wall of the opening 32 into contact with the quill.The end of spindle 35 is provided with a suitable head 38 to which canbe secured in any desired fashion, as by a nut, a headed screw, orotherwise, a rotating cutting element such as a cutting wheel 39.

The block 30 has a pair of dovetail shaped grooves 40 cut in the sidewalls thereof and extending from the top edge to the bottom edge ofthese side walls. As shown in Fig. 6 the grooves 40 are not straight butare of substantially arcuate shape being drawn each on a radius thecenter of which is a horizontal line passing through the center of thegrinding wheel 39. or in other words a horizontal line passing throughthe point 4|. Also the'side walls of the block 30 are provided with asecond pair of dovetailshaped grooves 42 near the rear end of theblock'which grooves are also of substantially arcuate shape from the topedge of the wall to the bottom edge thereof with the curvature beingformed on a radius also utilizing the same point 4| as a center.

Secured to the inner walls of the yoke are two pairs of strip members 45and 46 respectively. The members .45 are of trapezoidal shape incross-section and are curved along a radius corresponding to thecurvature of the grooves 40. llhe strips 45 are of such dimensions as tofit in the respective grooves 40 with a slight clearance. Each of thestrips 45 is held in assembly with the side walls of the yoke by threescrew members 41 passing through the extension part 25 of the yoke andthreadedinto the strip 45. The strips 46 are of similar shape incrosssection and are curved along the same radius as the grooves 42.These strips are held in assembly with the yoke by sets of screws 48.One screw of each set passes through the top of each side wall 22 andthe other two of which pass through the parts 2| of the column. Thesestrips 46 fit in the grooves 42 with the same clearance as the strips 45in grooves 40 so that when the screws 41 and' 48 are tightened, thestrips 45 and 46 are pulled firmly against the inner walls of the yokeand the bevelled surfaces of the strips are also brought into intimatecontact with the bevelled surfaces of the grooves so that the block isthereby firmly locked against any movement. When the strips are sotightened in the dovetail slots, they have a wedge-like action whichassures that the block cannot be moved while so locked. 1

As shown in Fig. 3, the block is capable of a tilting movement from ahorizontal position shown in full lines to the dotted line position,which movement is through an angle of approximately 30. This movementbeing about the center 4| causes a tilting of the grinding wheel 39 butsuch tilting is accomplished without a material change in the elevationof the cutting edge or periphery of the grinding wheel relative to awork surface supported on the chuck l4. Furthermore, if desired, bychanging the relative positions of the parts of the yoke, the angle ofmovement of the grinding element can be varied to other extents thanthat shown in the drawings. For example, upward movement of the blockabout the center 4| could be accomplished by raising the cap of the yokeand by extending the yoke walls upwardly, within limits. Thus, it willbe seen that the mounting of the block and of the grinding element forrotation about a horizontal line extending through the center of thegrinding block has the advantage of permitting angular variations in theposition of the grinding element without requiring any materialadjustment vertically of the column supporting the spindle block. Inaddition, the arrangement whereby the desired tilting is accomplishedhas the further advantage that the block is very efficiently locked inany adjustment position by the wedge-like action of the arcuate shapedstrips when the screws 41 and 48 are tightened.

As an auxiliary feature, the table II has a stand 60 at, one endthereof, which stand is hollowed out for the reception of an electriclight bulb or the like. The open part of the stand is covered by aground glass member 8| so that the rays of light from the bulb arediffused. This member serves admirably during setting up of work, inthat an operator can efllciently line-up the work on a chuck or othersupport. Also a guard 65 hasa throat part fitting around the quill 34and locked thereto by set screws 88, part of the guard 65 being shapedin the fashion of a hood as at 51.

From the foregoing it will be seen that the present invention provides anovel mounting for a spindle block in a surface grinding machine, whichmounting has the advantages of per mitting angular adjustment of thegrinding element without material variation in the elevation thereof andwhich mounting also has the advantage that the block can be moreemciently locked in any adjusted position than is customary witharrangements utilizing a spindle or other single mounting element. It isto be understood that the invention is capable of modification over theillustrated arrangement; in view of which any limitationsimposed'thereupon are to be only those set forth in the followingclaims.

What is claimed is:

1. In a grinding machine. a support for work to be processed, anelevator column having a yoke formation at the top thereof, a spindlecarrying block, spaced pairs of arcuate shaped guide members, means forsecuring said guide members in said yoke for limited movement relativethereto, said guide members engaging said block on the opposite sidesthereof for tilting movement of the block relative to the yoke, and aspindle carried by said block and extending beyond the same over saidsupport, the guide members of each pair having a common center wherebythe block is tiltable about an axis defined by a horizontal lineextending through said spindle near the end thereof over said support,said means for securing the guide members in the yoke being adjustableto lock the guide members in the yoke and to so grip said block as tolock the block in any adjusted position against movement relative to theyoke.

2. In a grinding machine, a support for work to be processed, anelevator column having a yoke formation at the top thereof, a spindleblock fitting closely within said yoke, and pairs of oppositely disposedguide members engaging the side walls of said block, releasable meansholding said guide members captive in said yoke whereby said block canbe tilted relative to said yoke, said pairs of guide members beingcurved on different radii having a common center which is forward of theend of said block and over said support, said releasable means beingadjustable to lock both the guide members and the block against movementrelative to the yoke.

3. In a grindingv machine, a support for work to be processed, anelevator column having a yoke formation at the top thereof, a spindleblock fitting closely within said yoke, and pairs of oppositely disposedstrips of trapezoidal shape in cross-section, adjustable securing meansfor holding said strips captive to the inner side walls of said yokewith a limited range of movement relative to the yoke, said block havingpairs of dovetail-shaped grooves to receive said strips, said respectivepairs of strips and grooves being curved on different radii having acommon center which is forward of the end of said block and over saidsupport, said securing means being adjustable to release the stripswhereby the block can be tilted and to lock the strips and block againstmovement relative to the yoke.

4. In a grinding" machine, a support for work to be processed, anelevator column having a yoke formation at the top thereof, a spindleblock fitting closely within said yoke, said block having pairs ofoppositely disposed .grooves in the side walls thereof, pairs ofoppositely disposed wedge members fitting in said grooves, and securingmeans for holding said wedge members captive to the side walls 01' saidyoke. said pairs of grooves and wedge members being curved on 10 PAUL V.MILLER.

